1. Field of the Invention
The present invention relates to a composite part, and a method of manufacturing the same, for use in an electronic circuit of a video tape recorder, wireless apparatus, radio receiver or the like.
2. Description of the Prior Art
It has been customary heretofore that each of circuit parts such as inductors, transformers, capacitors, resistors and so forth to be mounted on a printed wiring board for an electronic circuit is manufactured as an individual element or in the form of a composite part where two circuit elements such as an inductor and a capacitor are housed in a molded armor of synthetic resin or the like with connecting leadwires projecting therefrom.
However, the operation for mounting such a conventional circuit part or composite part on a printed wiring board is extremely intricate due to the existence of leadwires, and therefore a satisfactory result is not attainable technically with respect to the printed wiring board. And some inconvenience is unavoidable in handling as well because of relatively large dimensions of the conventional composite part mentioned above.
In a structure where a plurality of circuit parts are housed integrally in an armor, terminals for connection to an external circuit are provided individually for each circuit part, so that the mutual connection between the internal circuit parts housed in the armor needs to be shorted by the use of other leadwires or the like. This raises a problem that an additional time is required for mounting the circuit parts on the board. For solving the above problem, it becomes necessary to produce two types in the stage of manufacture, i.e. those with connected internal circuit parts and those with non-connected ones in conformity to individual uses, hence inducing a disadvantage of complicating the process of manufacture.
Furthermore, in a filter circuit composed of a plurality of combined circuit parts such as an LC filter circuit of an inductor L and a capacitor C combined with each other and housed in an armor integrally, a control member may be furnished for one of the circuit parts, e.g. the inductor to vary its inductance. However, even in such composite part, there still exists the aforesaid problem that two types of products having different relationship to connection need to be manufactured in accordance with individual uses as described above.
It is an object of the present invention to provide a composite part and a method of manufacturing the same, wherein a plurality of circuit parts can be integrated in small dimensions as a whole and formed into a lead-less type without any leadwire to consequently make a great contribution to improvement in the surface mounting technique, and still modes of connection between the circuit parts are alterable as desired in the stages of both manufacture and use.
And another object of the present invention resides in providing a composite part and a method of manufacturing the same with a function to adjust the electric characteristic thereof while realizing desired alteration of connection modes between its internal circuit parts in the stages of both manufacture and use.